: as of early May (2103), the Nook HD and HD+ devices can purchase apps (and other stuff) from the Google Play store. This change should make it possible to obtain CC for these devices.
-- Original FAQ answer, still appropriate for Nook Color and Nook Tablet:
We have received several requests to make Calibre Companion available in the Nook app store. Having been down this road before with Amazon, before spending time and money we asked B&N if they would allow CC into their store. A "NOOK Developer Evangelist" answered "no":
Officially, your app should be rejected as it provides a competing channel for book content. This can be appealed to management in the NOOKDeveloper group and you can make such an appeal by submitting a support ticket on the NOOKDeveloper site.
At this point we are putting the project on hold. Fighting with "management in the NOOKDeveloper group" isn't high on our list of priorities.
Sorry, folks, but it isn't our decision.